INS NYC 2024 Program

Poster	Poster Session 06 Program Schedule 02/15/2024 04:00 pm - 05:15 pm Room: Majestic Complex (Posters 61-120) Poster Session 06: Aging \| MCI \| Neurodegenerative Disease - PART 2 Final Abstract #95 Isolated, Stable Memory Impairment Following Bilateral Hippocampal Damage Secondary to Human Herpes Virus 6 Encephalitis (HHV6) in the Context of Bone Marrow Transplant for Pediatric Leukemia Bethany Schwandt, St. Jude Children's Research Hospital, Memphis, United States John Hamilton, Women's and Children's Center, Great Falls, United States Jennifer Longoria, St. Jude Children's Research Hospital, Memphis, United States Andrew Molnar, Monroe Carell Jr. Children’s Hospital, Nashville, United States Noah Sabin, St. Jude Children's Research Hospital, Memphis, United States Heather Conklin, St. Jude Children's Research Hospital, Memphis, United States Darcy Raches, St. Jude Children's Research Hospital, Memphis, United States Category: Memory Functions/Amnesia Keyword 1: encephalitis Keyword 2: bone marrow transplant Keyword 3: leukemia Objective: The historic case study of an adult patient (HM) who experienced severe anterograde amnesia following bilateral medial temporal lobectomy indicated the importance of the hippocampus in memory functioning. In the present case study, a pediatric oncology patient developed bilateral hippocampal lesions secondary to an acute human herpes virus 6 (HHV6) encephalitis. Further, epileptic episodes consistent with persistent sclerotic tissue in the mesial temporal regions emerged when the patient was well into remission, indicative of persistent injury. This patient provides a unique opportunity to examine the rare occurrence of focal lesions secondary to HHV6 in children, the role of the hippocampus in pediatric neurocognitive functioning, and the utility of serial neuropsychological monitoring for guiding intervention over time. Participants and Methods: A White male who was diagnosed with acute myeloid leukemia at age 7 was evaluated at age 11, 14, and 19 years old. He received chemotherapy, total body irradiation, and four bone marrow transplants (BMT). He experienced HHV6 following the third BMT. Initial MRI scans indicated stable encephalomalacia involving the hippocampal complexes, compatible with chronic sequelae of HHV6 infection. Follow up MRI (age 14) revealed mild mesial temporal sclerosis. EEGs were normal until he was 16 years old, when he began experiencing seizures. He used anti-epileptic drugs (AEDs) from ages 16-19. The patient initially underwent a comprehensive neuropsychological evaluation at age 11 years to assist with school re-entry after missing four years of school while undergoing treatment. He was reevaluated at age 14 and again at age 19 to assist with academic planning for high school and college entry, respectively. All neuropsychological scores were converted to standard scores and compared across cognitive domains over time. Within each cognitive domain, the assessments were averaged to account for some variability across batteries over time. Results: Neuropsychological test data are reported as standard scores (SS) with a mean of 100 and a standard deviation of 15. Scores between 85 and 115 are considered average. Across three evaluations, domains including language, visual spatial, motor, attention, executive functioning, academics, and adaptive functioning were all average (Standard Scores [SS] = 92-106). Relative to these age typical abilities, memory performance across domains (i.e., rote verbal, contextual verbal, visual) and memory functions (immediate recall, delayed recall, recognition) were below age expectation (SS = 75-79). Conclusions: The neurocognitive pattern of anterograde amnesia within the context of otherwise intact cognitive functioning is consistent with bilateral hippocampal lesions. Amnestic memory processes are well documented for humans and animals following medial temporal lobe damage, with deficits evident following time delay, secondary to interruption in memory encoding and consolidation. Findings from serial monitoring were instrumental in developing targeted memory interventions and recommendations to mitigate the impact of isolated memory impairment on functioning over time. Stable age typical academic and adaptive functioning skills over time may evidence how targeted, individualized interventions have supported the patient’s neurocognitive development. While memory deficits remained stable, with intervention and accommodations, the patient was able to maintain functional skills despite these challenges.

Poster

02/15/2024
04:00 pm - 05:15 pm
Room: Majestic Complex (Posters 61-120)

Poster Session 06: Aging | MCI | Neurodegenerative Disease - PART 2

Final Abstract #95

Isolated, Stable Memory Impairment Following Bilateral Hippocampal Damage Secondary to Human Herpes Virus 6 Encephalitis (HHV6) in the Context of Bone Marrow Transplant for Pediatric Leukemia

Bethany Schwandt, St. Jude Children's Research Hospital, Memphis, United States
John Hamilton, Women's and Children's Center, Great Falls, United States
Jennifer Longoria, St. Jude Children's Research Hospital, Memphis, United States
Andrew Molnar, Monroe Carell Jr. Children’s Hospital, Nashville, United States
Noah Sabin, St. Jude Children's Research Hospital, Memphis, United States
Heather Conklin, St. Jude Children's Research Hospital, Memphis, United States
Darcy Raches, St. Jude Children's Research Hospital, Memphis, United States

Category: Memory Functions/Amnesia

Keyword 1: encephalitis
Keyword 2: bone marrow transplant
Keyword 3: leukemia

Objective:

The historic case study of an adult patient (HM) who experienced severe anterograde amnesia following bilateral medial temporal lobectomy indicated the importance of the hippocampus in memory functioning. In the present case study, a pediatric oncology patient developed bilateral hippocampal lesions secondary to an acute human herpes virus 6 (HHV6) encephalitis. Further, epileptic episodes consistent with persistent sclerotic tissue in the mesial temporal regions emerged when the patient was well into remission, indicative of persistent injury. This patient provides a unique opportunity to examine the rare occurrence of focal lesions secondary to HHV6 in children, the role of the hippocampus in pediatric neurocognitive functioning, and the utility of serial neuropsychological monitoring for guiding intervention over time.

Participants and Methods:

A White male who was diagnosed with acute myeloid leukemia at age 7 was evaluated at age 11, 14, and 19 years old. He received chemotherapy, total body irradiation, and four bone marrow transplants (BMT). He experienced HHV6 following the third BMT. Initial MRI scans indicated stable encephalomalacia involving the hippocampal complexes, compatible with chronic sequelae of HHV6 infection. Follow up MRI (age 14) revealed mild mesial temporal sclerosis. EEGs were normal until he was 16 years old, when he began experiencing seizures. He used anti-epileptic drugs (AEDs) from ages 16-19. The patient initially underwent a comprehensive neuropsychological evaluation at age 11 years to assist with school re-entry after missing four years of school while undergoing treatment. He was reevaluated at age 14 and again at age 19 to assist with academic planning for high school and college entry, respectively. All neuropsychological scores were converted to standard scores and compared across cognitive domains over time. Within each cognitive domain, the assessments were averaged to account for some variability across batteries over time.

Results:

Neuropsychological test data are reported as standard scores (SS) with a mean of 100 and a standard deviation of 15. Scores between 85 and 115 are considered average. Across three evaluations, domains including language, visual spatial, motor, attention, executive functioning, academics, and adaptive functioning were all average (Standard Scores [SS] = 92-106). Relative to these age typical abilities, memory performance across domains (i.e., rote verbal, contextual verbal, visual) and memory functions (immediate recall, delayed recall, recognition) were below age expectation (SS = 75-79).

Conclusions:

The neurocognitive pattern of anterograde amnesia within the context of otherwise intact cognitive functioning is consistent with bilateral hippocampal lesions. Amnestic memory processes are well documented for humans and animals following medial temporal lobe damage, with deficits evident following time delay, secondary to interruption in memory encoding and consolidation. Findings from serial monitoring were instrumental in developing targeted memory interventions and recommendations to mitigate the impact of isolated memory impairment on functioning over time. Stable age typical academic and adaptive functioning skills over time may evidence how targeted, individualized interventions have supported the patient’s neurocognitive development. While memory deficits remained stable, with intervention and accommodations, the patient was able to maintain functional skills despite these challenges.